In a young married woman, the author observed that during her menstrual period, the gold ornaments which the patient wore would cause a dark discoloration of the underlying skin. The phenomenon manifested itself only during the menses; Ruehl convinced himself that no alloy, such as copper, had anything to do with this pigmentation; nor did perspiration play a role in its occurrence. Four cases of this kind are cited in detail; in all the discoloration of the skin began only after marriage; the discoloration was due to a deposit which could be washed off with soap and water, leaving the skin normal. The deposit began in the premenstrual period and persisted until the cessation of the menses. The author believes that certain chemical substances are secreted by the skin and that these exert a reaction upon the gold ornaments as they rub against the skin, forming a thin, black deposit underneath. In support of this theory many authors are quoted, giving proofs of the occurrence in intoxication phenomena during the premenstrual and menstrual periods. Poisons are eliminated, not only by the menstrual blood, but also by the salivary and the gastric glands, the kidneys, etc., and by the skin. The same phenomenon was observed in connection with platinum ornaments.